How to Calculate Backing for a Quilt
The top of your quilt is done, and you're asking yourself: "How much fabric do I need for batting and backing?" Ask no more — our quilt backing calculator is here with the answer!
Quilts are not only the perfect project for upcycling leftover fabric, but they're also a beautiful gift. You can use the quilting technique on clothes like skirts and jackets. The only thing that limits you when quilting is your imagination... and math. To make a quilt, you need three fabric layers: top, batting, and backing. We leave making the top to you and your artistic vision. Our quilt calculator will help you determine how much fabric you need for quilt backing and batting.
Quilt Batting
Batting, the middle of the quilt sandwich, is responsible for the warmth and weight of the quilt. Batting fabric is usually white or cream and made of polyester, cotton, wool, or bamboo. Each of the materials has its own properties: stiffness, thickness, washing guidelines, and stitching parameters. So, choose your desired batting material taking into account the quilt top design and the quilt's purpose. Afterward, use our quilt calculator to find out how much yardage you need.
Quilt Backing
Now, let's go to the bottom layer — the backing. Depending on your design, you can make it with one fabric, or more. Some quilters make their quilts two-sided. By using patchwork, appliqué, and other quilting techniques, the backing becomes a second top. Our quilt backing calculator tells you how much fabric you need for a simple one-fabric backing.
The fabric for quilt backing can be either directional or non-directional. If the material is directional, it means that it matters how you arrange one piece in relation to another — for example, you usually want all the flamingos facing the same direction. If you're using a non-directional fabric, it doesn't matter how you place the pieces.
How to Use the Calculator
- Choose your unit system — Imperial (inches/yards) or Metric (cm/meters).
- Enter your quilt top dimensions — width and length of the finished quilt top.
- Set the overhang — extra backing on each side (standard is 4 inches or 10 cm), so you have enough to square up the quilt after quilting.
- Choose your backing fabric width — Standard (44"/112 cm), Wide (60"/152 cm), or Extra Wide (108"/274 cm). Wide and extra-wide fabrics often eliminate the need for seams.
- Optionally add batting — the calculator will show the recommended batting size matching your backing.
- Enter fabric price (optional) to get a cost estimate in your chosen currency.
Understanding the Results
- Required backing size — the total dimensions your backing fabric must cover.
- Fabric strips needed — if your quilt is wider than a single fabric width, the calculator tells you how many strips to cut and sew together lengthwise.
- Total fabric needed — the yardage or meters to purchase, rounded up to the nearest 1/8 yard (0.1 m) to be safe.
Tips for Quilt Backing
- Always add at least 4 inches (10 cm) of extra backing on each side — this gives you room to square up the finished quilt.
- Pre-wash your backing fabric to prevent shrinkage after the quilt is finished.
- When joining fabric strips, press the seams open for a flatter result.
- Extra-wide backing fabrics (108" / 274 cm) eliminate seams for most quilt sizes and save time.
- The backing doesn't have to be plain! Use bold prints, stripes, or even pieced backing for a reversible quilt.